Gait analysis testing has been used to assist orthopedic surgeons in developing treatment plans for children with gait abnormalities, particularly children with cerebral palsy. Previous studies have shown that gait analysis testing significantly impacts surgical decision-making for these patients. However, no controlled studies have been done to determine whether gait analysis and the subsequent changes in surgical decision-making affect clinical outcomes. Consequently, the use of gait analysis in clinical practice remains controversial. The purpose of this study is to conduct a randomized controlled trial to assess the effects of preoperative gait analysis on surgical outcomes in ambulatory children with cerebral palsy. The specific aims are to determine whether the use of gait analysis data results in (1) greater improvements in walking ability and efficiency, (2) greater improvements in gross motor function, (3) greater improvements in overall patient well being and quality of life, and (4) less need for additional treatment compared with treatment provided when gait analysis data are not available. This study will be a randomized controlled trial. Patients will be randomized as to whether or not their preoperative gait analysis data are included in the treatment decision-making process. Comprehensive pre and 1-year postoperative gait analysis studies will be performed for all patients, along with gross motor function testing and questionnaires that assess a child's general health and well being. Postoperatively, the need for additional treatments will be assessed by an independent pediatric orthopaedic surgeon. 1-year outcomes will be compared between the patients whose gait data were available during the treatment decision-making process and the patients whose gait data were not available. The results will determine whether the use of gait analysis testing improves clinical outcomes in children who have walking problems due to cerebral palsy.